Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc

[sfrench/cifs-2.6.git] / kernel / kmod.c

diff --git a/kernel/kmod.c b/kernel/kmod.c
index 3d3c3ea3a023376f2ecf8c16b6c89aed39da67f4..a27a5f64443dc5c9a27d04679171cf15dfc1eabf 100644 (file)
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -51,8 +51,8 @@ char modprobe_path[KMOD_PATH_LEN] = "/sbin/modprobe";
 
 /**
  * request_module - try to load a kernel module
- * @fmt:     printf style format string for the name of the module
- * @varargs: arguements as specified in the format string
+ * @fmt: printf style format string for the name of the module
+ * @...: arguments as specified in the format string
  *
  * Load a module using the user mode module loader. The function returns
  * zero on success or a negative errno code on failure. Note that a
@@ -118,10 +118,10 @@ EXPORT_SYMBOL(request_module);
 struct subprocess_info {
        struct work_struct work;
        struct completion *complete;
+       struct cred *cred;
        char *path;
        char **argv;
        char **envp;
-       struct key *ring;
        enum umh_wait wait;
        int retval;
        struct file *stdin;
@@ -134,19 +134,20 @@ struct subprocess_info {
 static int ____call_usermodehelper(void *data)
 {
        struct subprocess_info *sub_info = data;
-       struct key *new_session, *old_session;
        int retval;
 
-       /* Unblock all signals and set the session keyring. */
-       new_session = key_get(sub_info->ring);
+       BUG_ON(atomic_read(&sub_info->cred->usage) != 1);
+
+       /* Unblock all signals */
        spin_lock_irq(&current->sighand->siglock);
-       old_session = __install_session_keyring(current, new_session);
        flush_signal_handlers(current, 1);
        sigemptyset(&current->blocked);
        recalc_sigpending();
        spin_unlock_irq(&current->sighand->siglock);
 
-       key_put(old_session);
+       /* Install the credentials */
+       commit_creds(sub_info->cred);
+       sub_info->cred = NULL;
 
        /* Install input pipe when needed */
        if (sub_info->stdin) {
@@ -185,6 +186,8 @@ void call_usermodehelper_freeinfo(struct subprocess_info *info)
 {
        if (info->cleanup)
                (*info->cleanup)(info->argv, info->envp);
+       if (info->cred)
+               put_cred(info->cred);
        kfree(info);
 }
 EXPORT_SYMBOL(call_usermodehelper_freeinfo);
@@ -240,6 +243,8 @@ static void __call_usermodehelper(struct work_struct *work)
        pid_t pid;
        enum umh_wait wait = sub_info->wait;
 
+       BUG_ON(atomic_read(&sub_info->cred->usage) != 1);
+
        /* CLONE_VFORK: wait until the usermode helper has execve'd
         * successfully We need the data structures to stay around
         * until that is done.  */
@@ -362,6 +367,9 @@ struct subprocess_info *call_usermodehelper_setup(char *path, char **argv,
        sub_info->path = path;
        sub_info->argv = argv;
        sub_info->envp = envp;
+       sub_info->cred = prepare_usermodehelper_creds();
+       if (!sub_info->cred)
+               return NULL;
 
   out:
        return sub_info;
@@ -376,7 +384,13 @@ EXPORT_SYMBOL(call_usermodehelper_setup);
 void call_usermodehelper_setkeys(struct subprocess_info *info,
                                 struct key *session_keyring)
 {
-       info->ring = session_keyring;
+#ifdef CONFIG_KEYS
+       struct thread_group_cred *tgcred = info->cred->tgcred;
+       key_put(tgcred->session_keyring);
+       tgcred->session_keyring = key_get(session_keyring);
+#else
+       BUG();
+#endif
 }
 EXPORT_SYMBOL(call_usermodehelper_setkeys);
 
@@ -444,6 +458,8 @@ int call_usermodehelper_exec(struct subprocess_info *sub_info,
        DECLARE_COMPLETION_ONSTACK(done);
        int retval = 0;
 
+       BUG_ON(atomic_read(&sub_info->cred->usage) != 1);
+
        helper_lock();
        if (sub_info->path[0] == '\0')
                goto out;